WO2005/082472 discloses an audio pacing device, configured to play an audio signal having a predetermined tempo. During operation, the audio signal can be selected for increasing, decreasing or maintaining a particular user exercise level of intensity. For example, such a device can be used to coach individual exercisers with a personalized training program.
Known personalized training devices as such are very helpful for people during their exercises, however when exercising outdoors, a group of exercisers will probably not be able to stay together if every exerciser follows his/her own personal training program.